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custom fiberglass surf boats

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URL: http://www.professorpaddle.com/forum/forum_posts.asp?TID=7341
Printed Date: 10 Jul 2025 at 6:55am


Topic: custom fiberglass surf boats
Posted By: Kiwi
Subject: custom fiberglass surf boats
Date Posted: 18 Sep 2008 at 9:53pm
my highschool requires a culminating project to graduate, only problem is it can't have to do with anything related to water or outside, (donkey basketball is on the list of restricted things) I thought that designing and then building a fiberglass surf boat would be a sweet cp, but I'm not sure how to go about it. does anyone have experence with building something like this? how much would it cost? do you use foam to mold a blank or something?



Replies:
Posted By: water wacko
Date Posted: 19 Sep 2008 at 8:40am
Kiwi, a friend of mine did one a couple years ago. Similarly, he had no experience, but just wanted to build one. A friend of his helped him, I think materials ran him about $400-500. I know there are books. One by local, Gary Korb I think. It looks pretty good. The foam was a B getting out. He used the pink rigid foam you can buy in sheets from Home Depot. Let us know how it's coming. Post some pics. Good luck!


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"Don't ask yourself what the world needs. Ask yourself what makes you come alive, and go do that, because what the world needs is people who have come alive." ~Howard Thurman


Posted By: Kiwi
Date Posted: 19 Sep 2008 at 8:58am
Yeah, I know gary, I think my best option is to go up to PA and check out his boats and talk to him. I've seen a couple of them. just looking around the internet I found the fluid element, maybe redesign that in fiberglass? idk.


Posted By: Kiwi
Date Posted: 19 Sep 2008 at 8:59am
and I'm only a sophomore, so it's not due till at the earliest, en of next year.


Posted By: Chuck e fresh
Date Posted: 19 Sep 2008 at 9:17am
That sounds like a sick little project . You shoul build a wooden paddle while your at it. I remember my high school had a boat shop. The fiber glass boat's that I saw being built had wooden skeletins ?? I'm sure boat building has advanced by now.  I sure would like to see how it's done though. Remind me to tell ya the joke about the wooden eye !!! Anyway take lot's of pics. Good luck !!

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There's no such word as can't!so stop making excuses!!!!


Posted By: water wacko
Date Posted: 19 Sep 2008 at 9:24am
I remember one of the problems he had was not putting enough clear coats on to stiffen up the sidewalls. It had some flex going on. Make that thing stiff!


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"Don't ask yourself what the world needs. Ask yourself what makes you come alive, and go do that, because what the world needs is people who have come alive." ~Howard Thurman


Posted By: dblanchard
Date Posted: 19 Sep 2008 at 3:10pm
I've been looking for help on this too. I found a pretty good write up on "The Gecko Boat" which seems really cool. The maker didn't take out all the foam, just enough form a cockpit:
http://www.ptone.com/Kayak/surfboat/building/

I'm interested in laying one up. Anyone else in the Seattle area interested? We could likely save some money (and frustration) helping each other out.

I couldn't find a Gary Korb book about boat building:
http://www.amazon.com/exec/obidos/search-handle-url/ref=ntt_athr_dp_sr_1?%5Fencoding=UTF8&search-type=ss&index=books&field-author=Gary%20Korb

Chuck e, let's hear the wooden eye story.

In any case, let us know how it works out for you and what spend on it. I found this on the cost of a cedar strip kayak and am trying to figure out how much epoxy and glass (or kevlar) I would need for a Gecko:
http://www.nessmuking.com/mykayak12b.htm

Good luck,

D


Posted By: Kiwi
Date Posted: 19 Sep 2008 at 5:48pm
yeah, that boat looks really good. I think I would skip on the fins though for durability.
also, I'm 6'5" and 200 lbs, what's a good length?
I like the design of the squashtail and incut sidewalls, but still want to be able to spin and maybe later get arieal, any ideas for that design?


Posted By: Kiwi
Date Posted: 23 Sep 2008 at 8:50am
no one?
come on...


Posted By: dblanchard
Date Posted: 23 Sep 2008 at 1:27pm
I have a Wavesport Forplay that surfs quite well, but sometimes pearls in smaller waves. It has a chine that is cut in a little, a bit like what you can see here:
http://images.google.com/imgres?imgurl=http://playak.com/images/boats/jackson-kayak/side-kick-2008.jpg&imgrefurl=http://playak.com/kayaks.php%3Fid%3D1195&h=450&w=176&sz=20&hl=en&start=11&sig2=fmtLqvJpEgQlEK_dr_5LZg&um=1&usg=__ED-po9h1AfLoBBFSvhTz-pld8lg=&tbnid=Cc_rGau8rWflDM:&tbnh=127&tbnw=50&ei=cEzZSIaPHIyipwT66ZWzBg&prev=/images%3Fq%3Dwavesport%2Bforplay%2Bkayak%2Bchine%26um%3D1%26hl%3Den%26sa%3DN
 
I think it gives me a better carve, but I don't think I could do 360s even if I knew how.
 
Other ideas could come from here:
http://surfyak.com/_wsn/page4.html - http://surfyak.com/_wsn/page4.html  - think I may buy the $40 DVD, but am undecided. I don't want a wooden boat, just a good design.
http://www.surfkayaks.com/products/surf/surf_frames.html - http://www.surfkayaks.com/products/surf/surf_frames.html  - I may just try to mimic one of these. Links to different boats are at the top.
http://www.clcboats.com/shop/boats/surf_boats/surfkayaks/CLC-MATUNUCK.html - http://www.clcboats.com/shop/boats/surf_boats/surfkayaks/CLC-MATUNUCK.html
http://www.duckworksmagazine.com/04/s/designs/church/woodyski/index.cfm - http://www.duckworksmagazine.com/04/s/designs/church/woodyski/index.cfm
http://www.orcaboats.ca/photopost/showphoto.php?photo=108&cat=531 - http://www.orcaboats.ca/photopost/showphoto.php?photo=108&cat=531  - ouch! That poor plywood.
 
Let me know what the rest of you find. Anyone else on this thread near Seattle? Also, are you all thinking ocean surfing, or river play?
 
D


Posted By: dblanchard
Date Posted: 23 Sep 2008 at 1:30pm
I just saw this explanation of shapes:
http://www.surfkayaks.com/products/surf/surf_frames.html - http://www.surfkayaks.com/products/surf/surf_frames.html


Posted By: Kiwi
Date Posted: 23 Sep 2008 at 3:35pm
mostly ocean waves. but if it works wll enough I might bring it to a park and play spot. I wouldent want to take a glass boat downriver.


Posted By: jP
Date Posted: 23 Sep 2008 at 9:53pm
I'm gonna weigh in here for this one: You want to build fiberglass/ kevlar kayaks?

First realize that it is unlikely that anything you produce on your first try will actually be something you want to paddle. I know I know, you're gonna say that you just want to build one boat, satisfy your criteria for school, ect,

I think that if you truly love to kayak, you should consider a slightly longer arc than the one you may be currently imagining. You should consider the possibility that it may take 3 boats before you come up with something really sweet. Check this out...

While there's talent here in the northwest (Gary Korb knows what's up), It is undeniable that the EAST is the MECCA for fiberglass whitewater boat building. From the earliest river runners, up through the 1980's, the art and science of glass boats became quite sophisticated and beautiful. The U.S. Slalom team was based out of Washington D.C., and people in nearby West Virginia, Friendsville Maryland, ect. experienced a BIG BANG of sorts. People Like John Sweet, Davey Hearn, The Snyder Brothers, Jesse Whittemore, to name but a few, refined and perfected the production process of lightweight, STRONG, high performance boats. The community was fertile and lots of ideas flourished. Few people know this, but some of those guys (Snyder & co.)were making proto types of really short, planing hull surf boats (very similar to modern playboat). I saw some of them when I was a kid. It's just that the slicy designs were what they were interested at the time (squirtboats), so that's what caught on.

I understand that you may not be able to make a full blown pilgrimage back there to learn the craft, but fiberglass boat building is a serious craft. You certainly do not want to try to reinvent the wheel, or remain isolated and spend your time and effort on something such as this without the right work shop, materials, and information.

The Very First place I would recommend is...
http://www.sweetcomposites.com

Davey Hearn has taken over John Sweet's company distributing material for boat builders. They'll be able to provide you with lots of valuable info too. I think it's awesome that you are interested in building boats. You may discover something really incredible. You can totally build a nice boat in a garage.

Do it! And once you get good at building them, build me one! I'll buy it from you.


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🐋🐋🐋🐋🐋🐋🐋🐋🐋🐋🐋


Posted By: jP
Date Posted: 23 Sep 2008 at 10:11pm
More than two cents more...

Why don't you want to paddle a glass boat on the river?  They don'e shatter when you hit rocks. Yeah, you can't just hammer them on rocks. But you can paddle all kinds of stuff. The Sky? no problem above 1000 cfs. The Green? O.k. it has its manky spots. The White Salmon? From BZ corners to Husum falls (including Husum falls) is good to go in a glass boat. Again, just don't expect to do any E.L.F. boating in a glass boat.

What happened to paddling skill? I'll tell you: Plastic boats came along and the skilll level of the average paddler has dropped significantly. People hit alll kinds of rocks because they can. But most of them can be avoided.

If you have a glass boat, you have an incentive to hit less rocks. With that comes a more sophisticated and refined paddling style. You can still slide over some domes and smooth rocks, but you generally DO want to be on familiar runs where you know the makeup of the river, it's true. You don't want a fiberglass creeker, for example. That's obvious. But a playboat? I think glass playboats would be rad! Rodeo Hole ain;t gonna beat up a boat when it's jiucy and fun in there.


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🐋🐋🐋🐋🐋🐋🐋🐋🐋🐋🐋


Posted By: Kiwi
Date Posted: 24 Sep 2008 at 8:51am
I think I'll try and make a trek up to PA too look at gary's workshop. thanks for all the info, I also have to come up with the funds. but I'll post pic's whenever I start building.


Posted By: franzhorner
Date Posted: 24 Sep 2008 at 12:22pm
I would love to have a fiberglass, surfboard like, floor for my Stiletto.  I wonder if the Snyder's ever played around with a fiberglass floor for their Thrillseekers!  I think having a fiberglass stiff and light board as my floor instead of the water logging three piece foam would be a HUGE improvement for my IK....

Nothing to do with the thread:::::

When I was at the Cheat a couple of years ago the guy at the campground/put-in said he would call his buddy Jim Snyder to find out what the flow was.  I said, Jim Snyder?  you mean THE Jim Snyder?  When Snyder heard we had duckies he told the guy to tell us not to go or that we better know what the hell we were doing and that it was pretty high for duckies.  We were looking to rent an IK too but he said no one he knows would do such a thing.  Instead, Aaron drove up to the Yock and rented a Thrillseeker and drove it down to the Cheat and back in one day.  That was not allowed by the company. 

The Cheat was awesome!

One thing about the East coast for sure is that either you are a hardshell kayaker or a river guide or both.  Anyone who is in a duckie is either new, a customer, a dumbass, or all of the above.  Also there are hardly any private rafters out there...


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MORE RAIN PLEASE


Posted By: jP
Date Posted: 25 Sep 2008 at 7:54pm
Actually, Franz, there's more private rafting than you think, it's just that the Shredder happens to be the local raftcraft of choice. The YOUGH is, after all where it was invented. The Cheat is a blast.

Yeah, there's predjudice against IK's pretty much everywhere. Boat Bigots can be found in all corners of the paddling world, saddly. The Snyders and lots of others pioneered lots of crazy steep creeks back there in Thrilseekers, as you all know. Some of those creeks were later run in hardshells, and some to this day have not been. I've seen video of those guys running drops in those things, slamming into boulders that were entirely unavoidable, and catapulting quite high into the air. Still some of the craziest shit I've seen on video.

And then there's "Striding" of course. Fish brought back a photo of one of Jeff's disciples running Pillow Rock in one. An "elevated" form of IK-ing, one might say.

I like your Fiberglass floor idea though! just make sure it's solid enough not to flex and splinter on ya. Nice concept.


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🐋🐋🐋🐋🐋🐋🐋🐋🐋🐋🐋


Posted By: Shape-changer
Date Posted: 26 Sep 2008 at 7:43am
If you are interested in shaping a boat I can walk you through the process and tell you where to get materials. I am currently working on a boat right now.
Cheers


Posted By: Shape-changer
Date Posted: 26 Sep 2008 at 7:57am
I uploaded two pictures a the boat I shaped last month
Cheers


Posted By: H2Ohta
Date Posted: 26 Sep 2008 at 8:23am
Kiwi, you should speak with Shape-changer.  His boats are pretty much what you are describing and he has produced some excellent glass play/surf boats.  His boats have proven river worthy and have torn up the biggest waves the Wenatchee has to offer.  I am currently waiting for production of his new boats as I hope to buy one when they are available.  Drop him a PM and his real name is .... (his identity will remain safe with me).
Chris Ohta


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H2Ohta


Posted By: dblanchard
Date Posted: 26 Sep 2008 at 10:27am
Wow, Shape-changer. Beautiful design. I'm still trying to decide whether to commit to this type of project. Can you tell me about how much you spend on materials for each boat and about how long it takes to shape one? I know it would take me much longer as a novice, but I'd like to know your time as a minimum for me.  Also, are your molds left in the boat, or are they reusable?

Thx,

D


Posted By: Kiwi
Date Posted: 26 Sep 2008 at 12:49pm
whoa, that boats looks pretty much perfect, has anyone seen the new wavesport project 54cx? it's composite and weighs 19 lbs.


Posted By: chuckj
Date Posted: 27 Sep 2008 at 4:05am
Gary has a  video that he sells for $10.00. Basically the cost of the cassette.
I've built 2 surfkayaks using his method with mixed success. The problem being in the design rather than the construction.
The basic principle is to make a plug out of pink insulation foam and then drape your glass over that, usually 4-5 layers of 9oz glass and SB-112 epoxy.
Getting the foam out is a problem, depending on the construction method you use.
 
It's a pretty bare bones method of building but does work well. Friend of mine just finished a SOT surfkayak using Gary's method. Seems like it was easier to build and took half the time.


Posted By: Shape-changer
Date Posted: 27 Sep 2008 at 4:13pm
Hey D cost is going to be different depending on if make a one off using a process like this; check this out: http://www.ptone.com/boatbuilding2002/ or shaping the design and making a mould to make multiple boats from. So, unless you plan on selling a few before the next version or making two, three, four, five protos and still be able test the original against the new versions; the one off process is the cheapest and quickest to make a boat and get on the water.
As far as time, I don't shape professionally any more but, I think it took me 50 to 60 hours from sketches to finished shape not including glassing and mould making and building an actual boat.

Cheers



Posted By: jP
Date Posted: 27 Sep 2008 at 10:12pm
WOW! that's great to see those photos. nice looking design. It reminds me of a boat I saw back in PA when I was a kid. --a "surf shoe" Greg Green called it.

chuckj: you mentioned that the pink foam was hard to get out. what if you wrapped it in plastic wrap before laying up your glass layers? would that provide an adequate separation between fiberglass/resin and foam? I remember watching guys lay plastic film (like Ceran Wrap) over patches, ect, and later after the resin is hard the Ceran Wrap just peels right off.

Anyway, I'm stoked on this thread!!! This is what this site should be for: actual knowledge and info sharing. In fact, It's got me excited about glass boats. I may take my old fiberglass boat out to the Sky tommorow. Maybe soon I'll undertake the project of restoring it. (got some sh*tty patches that need grinding and re-doing).

I'd like to make a boat, too at some point.


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🐋🐋🐋🐋🐋🐋🐋🐋🐋🐋🐋


Posted By: chuckj
Date Posted: 27 Sep 2008 at 11:16pm
Mmm! The bond between the epoxy and the pink foam isn't the problem, it's accessing it. Once you start to get around the calves and feet you're pretty deep into the boat and unless you're small, which I'm not, you can only work with one arm/hand. It's not impossible but can be painfully slow and laborious. You could also just chuck a quart of acetone into the boat and wait.
What I did end up doing was  a single layup of 9 oz glass then cutting out the cockpit, glass, pink foam and all, removing the pink foam(CAREFULLY!) from the cut out section then replacing it. I then put on a 5 oz layer of glass to keep this in place and finished the glassing process.
 
 


Posted By: Kiwi
Date Posted: 28 Sep 2008 at 9:42am

I really want to start building but I have 0 cash, I guess I need to spend some more time on the plans, but I think I'll go with a little longer 8' or so boat.



Posted By: Shape-changer
Date Posted: 28 Sep 2008 at 3:22pm
Kiwi, you should buy some graph paper if you don't already have some and tape together enough pieces so that you can draw your plans to half scale or half inch = an inch. That way it will be much easier to convert to full scale later and once you have a good outline/top view and a good deck profile, parting line & rocker profile you can shape a scale model. This way you don't money on a big blank of foam your first time. Also, you will learn a lot about the process of shaping and you may decide to change the design along the way. I wouldn't go any small on the scale because it gets really hard to see the detail.

As far as the length of your boat in reference to an earlier statement about wanting make a squashtail and still be able to get some air. I think 8' may a little long; even at your height and weight you don't need to go any longer than 6'-6" maybe 6'-8" if you have really big feet. Maybe do a little research about surf board design and include that in the written part of project. I believe this help the development of your design.

Cheers-


Posted By: Kiwi
Date Posted: 28 Sep 2008 at 9:17pm
okay, will do. currently I'm working on test corrections for my honors bio class, I have to write 6 pages by tuesday, and it is just a blast.


Posted By: chuckj
Date Posted: 28 Sep 2008 at 11:12pm
Kiwi
If you're doing a playboat then a shorter boat would do but if you're intent on a surfboat then there are a couple of things to consider and Mega gives a pretty good overview
http://www.surfkayaks.com/products/surf/surf_frames.html - http://www.surfkayaks.com/products/surf/surf_frames.html
Looking at surfboard designs, as Shapechanger suggested would help but looking at the design of waveskis would probably give you a better idea on design of a surfboat.
Boatertalk's "Surfzone" is a good place for input as there are a couple of designers and builders that lurk, including Gary.
 
Good luck! you're embarking on a marvellous project that will frustrate the hell out of you and keep your mind occupied for hours. You'll spend about 3 weeks building the boat but about 3 months designing it as you become aware of the tradeoffs.


Posted By: chuckj
Date Posted: 28 Sep 2008 at 11:28pm
One more thing...try and get your bum into a couple of boats which may be a little difficult with your size. SurferDave down at Westport http://www.surferdave.net/index.html - http://www.surferdave.net/index.html  runs a couple of demo Mega kayaks. OlallaDave is a big fella on the peninsula who has a  Megatron and if you can get hold of a fellow called Rob Casey, he has a Dick Wold Bigmachine.
Of course you're welcome to try my Alamax and the semi working surfboat I built.


Posted By: Kiwi
Date Posted: 29 Sep 2008 at 8:44am
that megaron looks exactly like what I was thinking.
I think I'll try to steal that design. and It's just under 8 feet.
thanks


Posted By: dblanchard
Date Posted: 29 Sep 2008 at 9:17am
Getting the foam out of the Gecko <http://www.ptone.com/Kayak/surfboat/building/> boat was done using a drill with a wire brush. While that is faster than using the spoon on my Swiss Army knock-off, it still seems like a lot of work. Also, I'd have to shape a new blank and go through the hollowing out process again for each additional boat.

I don't need to make a bunch of boats, but I have a bunch of friends who would likely be interested to get into WW if the cost of entry were lower.

So, I'm interested to hear whether anyone has had luck, or thinks I might have some, buy first shaping a boat and putting on a single ply of glass and calling this my mold. Then spraying it with PVA (mold release) and making two "halves" (top and bottom) of a new boat, one at a time,  on the mold and joining them after they are both fully cured.

I see that I would have some potential for weakness along the seam, which would be around the widest part of the top of the boat, but I think this could be mitigated by just doing a few plies for each half, then some strong seam tape, inside and out,  and the rest of the external plies on top of that.

I'm actually thinking of a whitewater design and depending on the design, even half a boat may be hard to get off the mold, but I think I can design around that and even if I had to cut parts of the first two plies to get it off, those parts could be reinforced before putting on the remaining plies.

I'd use Jackson's outfitting on top of some closed cell foam build-ups for the seat and feet.

Anything I'm missing?


Thx,

D


Posted By: Chuck e fresh
Date Posted: 29 Sep 2008 at 10:00am

Mmmm hmmm....



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There's no such word as can't!so stop making excuses!!!!


Posted By: dblanchard
Date Posted: 29 Sep 2008 at 4:15pm
Kiwi,

The graphpaper suggestion above is right on the mark. Once you have a design worked out the way you want I think scanning it and projecting it from your computer onto your foam block may be the easiest way to transfer it. Your school surely has some projectors you could get access to.

I'm thinking of starting with one of these two designs and may just do my first mold with no modifications other than a couple to make the mold easier to release. The pages have good top-down, front, back and side views that I can project onto each side of my block and trace out in magic marker. Of course, I couldn't sell any boats made with Fluid's designs, but that isn't really a goal anyhow.
http://www.fluidkayaks.co.za/Whitewater_M-Nemesis.htm
http://www.fluidkayaks.co.za/Whitewater_Element.htm

I'm leaning toward the Nemesis - has anyone paddled one?

Thx,

D


Posted By: Kiwi
Date Posted: 29 Sep 2008 at 4:25pm
yeah, my dad's a art teacher, so I already have a projector, that's a good idea.
finished with the test corrections and now am doing ap world history. but I still have to talk to the cp head to see if I can start it this year.


Posted By: dblanchard
Date Posted: 29 Sep 2008 at 4:33pm
I was thinking that I could completely seal off the stern and not use float bags, but I'd miss being able stuff things back there and that led me to thinking of a hatch, but I'd want it water tight and easy to open and close with one hand.

Any ideas?

D


Posted By: Kiwi
Date Posted: 29 Sep 2008 at 9:45pm
hatches belong in sea kayaks, IMO.


Posted By: chuckj
Date Posted: 30 Sep 2008 at 8:45am
One caveat with using a single layer as yer mould is that fiberglass distorts slightly as it cures. If you are planning on making a mould I would use more than one layer.


Posted By: rainpaddle
Date Posted: 30 Sep 2008 at 2:58pm
Kiwi,
 
At 6', 5" I'm guessing you have some pretty long legs. I have a Mega Impulse which fits my 36" inseam well. It is about 7' 8"s long and 27"s wide which floats my 230 pounds ok. The deck height is adequate at maybe 14 inches.
 
Gary Korb is definately the master at surf boat shaping. Take really good notes on where his bow rocker and rail configuration starts. My rails on the impulse are very sharp but due to my weight they sit under water amid and it is a little tippy until I plane.
 
Also, take good notes where you put your fin boxes. I like the adjustability of the Mega fin system and it is interesting to see what differences it makes to slide them up and down the track depending on conditions.
 
I have 2 boats and you are welcome to come over and check them out. Mega's site is http://www.surfkayaks.com - www.surfkayaks.com .
 
Cheers,
 
Rob G


Posted By: rainpaddle
Date Posted: 30 Sep 2008 at 3:01pm
One more thing:
 
I use Jackson Happy Feet for my foot bag as it gives me a degree of flexibility if someone else is in the boat. It is also comfy.
 
Cheers,
 
Rob G


Posted By: Kiwi
Date Posted: 30 Sep 2008 at 7:53pm
I have a 36" in inseam too.
whoa!!!


Posted By: chuckj
Date Posted: 01 Oct 2008 at 1:50am
Kiwi
If you can try and get into a Megatron before you decide. I'm 6'6"  205lb with a 36" inseam and size 14 feet, the Megatron felt BIG and clunky. It definitely is a big persons boat.
Something like the Scarab, which is a size down from the Megatron may work.


Posted By: Kiwi
Date Posted: 01 Oct 2008 at 8:58am
okay, I'll look around.
so, are fins necessary?
can you build a surf boat without them?


Posted By: chuckj
Date Posted: 01 Oct 2008 at 3:49pm
You certainly can build a boat without fins but why not give yourself the option. Putting in finboxes really is pretty easy  and you will be surprised at the difference they make especially in down the line drive and a s a pivot point when turning.


Posted By: Chuck e fresh
Date Posted: 01 Oct 2008 at 7:37pm

Go with fin's, there's a reason why surfboard's have them. At least your's will be removable.



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There's no such word as can't!so stop making excuses!!!!


Posted By: Kiwi
Date Posted: 06 Oct 2008 at 8:35pm
well, after all of that, it turns out doing your cp as a sophomore is against the rules.
so the earliest I can start it would be the begining of the summer, june 20th.
the whole cp system is f*cked, the list of prohibited Items is 3 pages long and limits you to observing a cardbord box biodegrade.
 
anyway, I went surfing at westport on sunday!!!
8 ft. swells 16 sec.
even made up a new move, the waterscrew!!!
just find the biggest wave you see and lean away from it so you go into a uncontrolled tumble into the beach, as long as you end up in a sidesurf eventully you've succeded!


Posted By: jP
Date Posted: 04 Sep 2009 at 10:54am
AHA!! I FOUND IT!

BUMPA!

now I don't owe anyone beer or OJ!
I'm bumping this thread to keep it handy and near the surface.



Posted By: rokmnky
Date Posted: 04 Sep 2009 at 2:17pm
I know this is an old thread but a quick thought for anyone looking. What if you took your foam blank and cut it into sections then put it back together with short dowels so that you can disassemble it to pull it out in pieces after the glass cures. It would definatly be alot of work but might make it so that you can use it multiple times.

Any thoughts?

Also, besides home depot is there anywhere to get large blocks of foam around here? and is there a better type of foam to use? I'm guessing the less porous the better.


Posted By: dblanchard
Date Posted: 04 Sep 2009 at 3:35pm
On the contrary, I would use a rather porous foam so that shaping it goes faster. Then before I glass it, I'd coat it in wax or putty or something to keep the resin from absorbing into it.

I think shaping a plug as a whole would offer the best result, but then glass and cure the top "half" as a separate process from the bottom half and fit the two shells together as a final step. They wouldn't really be halves, as you would want to keep the edge to the widest part of the boat. This would also let you easily add hardware for mounting seats, grab loops, etc. before joining the two shells.

If you are looking at using a plug, I would also consider making prototype boats out of the cheapest glass you can find, then when you have a design dialed in the way you want it, create your "production" boat in something sturdier.

As for sources, there is/was a foam store on Roosevelt in Seattle. I've never been inside, and don't know whether it is still there, but it is worth a look.


Posted By: rokmnky
Date Posted: 05 Sep 2009 at 7:21pm
This thread really got me thinking about building an ocean surf kayak. Does anyone in seattle have one I can come look at for some inspiration?


Posted By: dave
Date Posted: 06 Sep 2009 at 10:29am
Easy Rider has one at their shop you can look at.

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Nomad


Posted By: chuckj
Date Posted: 06 Sep 2009 at 9:11pm
I do!


Posted By: TastyWaves
Date Posted: 08 Sep 2009 at 7:54pm
hey man, I have some shaping experience but for surf boards. For a boat you would just need to start with one of the thickest blanks (a big foam board) and then shape according to your own desires. For all your foam/resin/glass/monomer/decals/Q-cell/sanders, everything you need to work with high performance fiberglass, here is a great website to find everything you need, including shaping videos:

http://surfsource.net/Manufacturing/indexx.htm

The owners of Surf Source are out of Jacksonville, Florida, super knowledable, they'll be glad to help you with any of your questions.


Posted By: jP
Date Posted: 09 Sep 2009 at 5:43pm
awright: much to my dissappointment, despite the infinite proliferation of info on the wacky worldwide web, despite much searching for info on this subject far and wide, (some of) the best info yet I've turned up happens to be from Sweet Composites...
This link below talks about making plugs and molds.

http://www.sweetcomposites.com/Mold.html

I'm so turned off by the idea of having chunks of pink foam left behind inside the boat, that I think I'd be willing to go ahead and make a mold from the plug and then layup a boat inside that. Sure it would take longer, but the end result is what matters most.

Of course, the whole boatbuilding thing is still a pipedream at the moment, but it keeps nagging at me.



Posted By: dblanchard
Date Posted: 10 Sep 2009 at 8:38pm
This pair used acetone to eat out the foam.
http://www.ptone.com/boatbuilding2002/page1.html
I'm not sure how eco-friendly that is, but it would make for an easier job.


Posted By: Shape-changer
Date Posted: 11 Sep 2009 at 6:20am
Making a plug and then making a mold is a good way to go because if you change your plug afterward and make v2, v3 or v4 you can always go back quickly especially if you break the first prototype. The molds can pile up but its an accurate record of what you have all ready done. On another note pouring acetone inside is a very dirty process and takes more acetone than you think to get it all out. Also, what doesn't come out is now hard as a rock. So, unless you have lots of acetone and unlimited access to hazardous waste dumping I don't think its a good choice.
Cheers-


Posted By: jP
Date Posted: 11 Sep 2009 at 2:30pm
I've also heard that it's not really good to have all that acetone against your work. It erodes the foam, but also weakens your laminates.


Acetone is the solvent used against epoxy for cleaning up tools ect. I've read that while it's an accepted practice to pour it in to your foam to get it out, it makes a mess.

Personally I'd rather find and alternative, but then again, I'm not a boat builder, so I don't really know from experience. I know that the boat builders I knew growing up never did that. They had more sophisticated techniques that avoided that step in the process all together.


Posted By: dblanchard
Date Posted: 19 Nov 2009 at 1:34pm
I'm still very interested in doing this, so, I'm dumping all my ideas and questions on the group.

I've got a design mostly worked out in Kayak Foundry, but would like to know what other tools people are using for design. Because of the limitations of KF (it is really intended just for sea kayaks), I'll end up having to use pencil and paper, or just an image editor to make some refinements.

I have read in various places that:
a. the

I still need to paddle a bunch of different boats to make some design decisions, so I'll hit everyone up for loaners soon.

One thing I have only now started considering is seat height. A higher seat would give me more reach and mobility above the boat, but would cause a higher center of gravity. I'd love to hear all your thoughts on seat height.

Summing up some other ideas, I agree with Shape-changer and jP that a two piece casting from a reusable mold is the way for me to go.

I think the standard is to use two-pound rigid polyurethane for the plug. Any suggestions on where to get a big block of it, or at least pieces to glue into a big block. In that case, what type of glue should I use?

Should the plug be glassed, or is just having it puttied and sanded smooth enough? It seems that puttying and sanding would be less work than glassing it, but I really don't know.

The mold will need to be at least a couple plies thick to prevent distortion from shrinkage during curing.

Would someone please tell me how many plies they think the mold should be? And for that matter, how many plies should the boat have? It sees to me that the deck shouldn't need to be as thick as the hull, but maybe that isn't true.

Since I want to have a copy of my final version last me a good long while, I'll eventually need to make repairs. Additionally, I may need to "fix" some elements even while it is brand new. It occurs to me that by tinting the epoxy one color for the first few plies and then another color for the last few plys, it would be easy to see how far into the boat I have sanded for repairs. Any comments on that?

The finished plug needs to be a tad bigger than the actual boat will be because of shrinkage when I glass the plug, and additional shrinkage in the mold when it cures.

I shouldn't make any edge too radical because of the stiffness of the fiberglass.

Fiberglass comes in S-glass (strong-glass) and e-glass (electrical glass). Using S-glass seems like the obvious choice.

Carbon is said to be rather weak compared to fiberglass, though kevlar, or a fiberglass-kevlar blend may be an option for me.

I have never laid up any kind of composite. I know an accelerant can be used so that the cure time is shorter, and that adding too much accelerant can cause "spontaneous combustion." Still, I have no idea how long a cure might take with no accelerant, or with a modest amount.

Also, can two or more plies be wetted out at the same time? This seems like a bad idea, but I really don't know.

I think that orienting each ply 45 degrees offset from the previous ply makes the most structural sense. Is there any reason not to do this?

Do I need to sand each ply down after it has cured? Does this make more sense for the boat than for the mold or for the plug?

I'm still pretty tempted put a hatch in, but I don't know yet.

Alright, I know a lot of you are smarter than me, and all of you are at least as experienced as I, so let's hear your thoughts, criticisms, and suggestions (and encouragements).


Posted By: dblanchard
Date Posted: 19 Nov 2009 at 5:08pm
Hmmm. I hope everyone is busy planning their weekends. I hurt my shoulder last weekend biking, so I have been dreaming of building a boat instead of planning to get wet.

Rereading < http://playak.com/index.php?option=com_content&view=article&id=1243%3ADesign+and+build+your+own+WW+kayak!&catid=1142%3AArticles&Itemid=39 - Håkan Haver's article > I see that for his boat he used two plies of 450 gram fiberglass on his deck and three plies of the same on his hull.

Do any of you know whether that seems too lightweight or not. I'd like to know how whether a single ply of fiberglass with a single ply of kevlar over it would be as strong as his three plies of fiberglass. Any guesses, or dissuasions?

Thx,

D


Posted By: Shaun
Date Posted: 19 Nov 2009 at 7:05pm
Well, here are my thoughts. This is what I have found out while making a bunch of slalom boats and home made play boats.

Originally posted by dblanchard



One thing I have only now started considering is seat height. A higher seat would give me more reach and mobility above the boat, but would cause a higher center of gravity. I'd love to hear all your thoughts on seat height.


I would certainly make a seat where you could change the height. On one boat that I made, I made a foam seat that sat on the hull, and I could change the amount of foam that was under it to change the height. This was for a surf boat also, so I wasn't afraid of having a rigid spot on the hull because I wouldn't be running it over rocks.


The mold will need to be at least a couple plies thick to prevent distortion from shrinkage during curing.


There won't be shrinkage because it will cure to the exact size of the plug. Then the boat halves will be the exact size of the mold. There is in plastic boats, but not fiberglass boats. You do want a stiff mold to make sure the final boat isn't twisted or anything.

Would someone please tell me how many plies they think the mold should be? And for that matter, how many plies should the boat have? It sees to me that the deck shouldn't need to be as thick as the hull, but maybe that isn't true.

How I have always done molds, is to make the first layer glass to get a great smooth first layer, and then use inexpensive mat to complete the plug. There is no reason to use anything expensive for a mold other than the first (maybe second) layer. You want the mold to be stiff, so the more the merrier with the mat. I would do 5 layers at least over the S-glass first layer. Almost all molds are black so that you can see any imperfections in the mold.

For the final boat, it depends on how light you want it and what materials you want to use. For a midweight boat, I would do: glass, kevlar, carbon, carbon for the hull, and glass, kevlar, carbon for the deck. The carbon can be replaced with glass for a large $ savings, and a small weight gain, and a small loss in stiffness.




Since I want to have a copy of my final version last me a good long while, I'll eventually need to make repairs. Additionally, I may need to "fix" some elements even while it is brand new. It occurs to me that by tinting the epoxy one color for the first few plies and then another color for the last few plys, it would be easy to see how far into the boat I have sanded for repairs. Any comments on that?


You should be able to tell how far you have sanded into the boat by the change in stiffness of the area, and often times, you can see the layers as you sand through them. Don't use Kevlar if you want to sand the boat other for repairs, though. When you sand Kevlar, it fuzzes something fierce. Also, if the boat fractures, you want to grind out the entire fracture, not just a layer or two, so it won't be very important to know how far you are sanding through the boat anyways.

I shouldn't make any edge too radical because of the stiffness of the fiberglass.
   I have had sharp edges on fiberglass boats without issue before. The worst part about it is getting the glass to lay in there while laying up the boat, but that is where bias cut glass saves the day.

Fiberglass comes in S-glass (strong-glass) and e-glass (electrical glass). Using S-glass seems like the obvious choice.

Carbon is said to be rather weak compared to fiberglass, though kevlar, or a fiberglass-kevlar blend may be an option for me.


S glass is what you want.

Carbon is stronger than fiberglass for the same weight. If someone told you differently, you might want to check what they tell you in the future. Carbon is more brittle than glass, but is stronger and stiffer. One layer of 6 oz carbon will be stiffer, stronger, and lighter than one layer of 6oz s glass.

Kevlar is also very strong, but flexes well. This is why it is good in whitewater boats, it can handle hitting rocks better than glass and carbon (it will flex instead of break). However, it doesn't help making the boat very stiff. Also, Kevlar is a bastard to work with. It is near impossible to cut without the $75 kevlar shears, and it fuzzes when you sand it.



I have never laid up any kind of composite. I know an accelerant can be used so that the cure time is shorter, and that adding too much accelerant can cause "spontaneous combustion." Still, I have no idea how long a cure might take with no accelerant, or with a modest amount.


Accelerants are more common in polyester resins, and I recommend using a good epoxy resin without accelerants. I use 3M epoxy and like it much better than any polyester. The resin gets jello like in around maybe 30 minutes or so depending on temperature, so I mix in smaller batches to avoid waste.

Also, can two or more plies be wetted out at the same time? This seems like a bad idea, but I really don't know.

You can, but it can turn into a disaster sometimes. The first layer should be done alone to make sure you have a good layup without air bubbles. If you are using light weight materials, you can do more than one at a time, but I wouldn't. If you are going to vacuum bag, then you do them all at the same time, but I wouldn't try it your first time.


I think that orienting each ply 45 degrees offset from the previous ply makes the most structural sense. Is there any reason not to do this?

Do I need to sand each ply down after it has cured? Does this make more sense for the boat than for the mold or for the plug?


The amount of a pain that it would be to offset the weave of the glass 45 degrees will be about 100x more of a pain than it would be worth.

Don't sand between layers on a layup. Don't even bother letting it cure unless you need to. You want to avoid getting contamination between the layers, because they have a chemical bond. What I do is the first layer with great detail to make sure the final product is going to be perfect. The first layer can be layed down with a little extra resin. Once you are happy, drop the next layer on it. It will soak up much of the spare resin from the first layer, you will still have to add extra to get it completely saturated. The last layer, you want to try to work out as much of the resin from the lower levels as you can to avoid extra resin (weight), but make sure it is completely saturated.


Posted By: Shaun
Date Posted: 19 Nov 2009 at 7:11pm
Originally posted by dblanchard


RereadingI see that for his boat he used two plies of 450 gram fiberglass on his deck and three plies of the same on his hull.

Do any of you know whether that seems too lightweight or not. I'd like to know how whether a single ply of fiberglass with a single ply of kevlar over it would be as strong as his three plies of fiberglass. Any guesses, or dissuasions?


That seems very light for a boat to me. A lightweight slalom kayak would be glass, kevlar, kevlar for the hull and glass, kevlar for a deck, and that would be a boat that I would expect to be fixing all the time. Not to mention it would be very flexable to the point of oil canning while paddling it. For what you want, you want to do a stronger layup than that. Remember that Kevlar isn't going to add a lot of stiffness to a boat, it is more for impact resistance, but it will add stiffness, just not nearly as much as carbon. A glass carbon deck would probably work for a very light boat, but you will want a stronger hull for sure.


Posted By: dblanchard
Date Posted: 23 Nov 2009 at 10:05am
Thanks Shaun, and everyone, for your excellent input.

I reread my other message on carbon, and that person was just saying carbon is more brittle than the other materials.

Shaun, you suggested glass, kevlar, carbon, carbon for the hull, and glass, kevlar, carbon for the deck for a mid-weight boat. I understand this to mean the glass would be the first ply to go on to the mold for each, and the carbon would be the last ply to go over the mold. Is that correct?

Since I have all options available at this point, what would be the optimal hull, prioritizing strength/durability over weight? Would glass, kevlar, glass, kevlar be structurally different in any way than glass, glass, kevlar, kevlar? Would either of these provide enough stiffness? From Shaun's post, I gather that glass, kevlar, glass, glass is probably best, but I want to be sure. Also, does that assume 450 glass?

As Shaun pointed out, the bulk of the weight comes from the resin. I see now that I had previously made too much of an issue of the materials' weights. I'd really rather have a strong stiff boat, even if it weighed as much as my plastic boat, though I'd be very happy to have a lighter boat.

Thx,

D


Posted By: jP
Date Posted: 23 Nov 2009 at 4:43pm
Thanks Shaun for the input, for sure- I'm interested in all this too, but lately I've been putting more time into boating and planning trips. Definitely want to keep this info onhand though.

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🐋🐋🐋🐋🐋🐋🐋🐋🐋🐋🐋


Posted By: dblanchard
Date Posted: 01 Jan 2010 at 11:01pm
UKC is hosting a workshop on repairing composite boats at the Seattle REI on 1/22/10.

< http://www.washingtonkayakclub.org/index.php?option=com_content&view=article&id=181:fri-jan-22-2010-general-presentation - Details >


Posted By: iron monkey
Date Posted: 02 Jan 2010 at 12:14am
if you wanna build a boat get a copy of charlie walbridge's boat builders manual off amazon about $10, and it will answer 90% of your  questions



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